ametropia vs visual disorder

ametropia and visual disorder both are nouns.

Word	Noun	Adjective	Verb	Adverb
ametropia	Yes	No	No	No
visual disorder	Yes	No	No	No

As nouns, visual disorder is a hypernym of ametropia; that is, visual disorder is a word with a broader meaning than ametropia:

ametropia: (ophthalmology) faulty refraction of light rays in the eye as in astigmatism or myopia
visual disorder: impairment of the sense of sight

Other hypernyms of ametropia include vision defect, visual defect, visual impairment.

ametropia (noun)	visual disorder (noun)
(ophthalmology) faulty refraction of light rays in the eye as in astigmatism or myopia	impairment of the sense of sight